A bulb comprises a seat; a plurality of metal heat sink each having two fixing surfaces, one fixing surface being fixed with an light emitting chip; and one end of each metal heat sink being placed into an insulated frame and then being fixed to a supporting surface of a heat conductive base; the metal heat sinks having an effect of absorbing heat energy and then transferring heat to the seat so as to dissipate heat; the metal heat sinks being integrally formed with the bulb base and then being combined to the seat; the heat conductive base having an inclined surface which is advantageous to reflect light from a light emitting diode so as to increase the illumination of the light emitting chip; and a metal adhesive layer being assembled to the supporting surface of the heat conductive base and the fixing surfaces of the metal heat sinks.